Significance of the difference between two correlation coefficients
Adaikalavan Ramasamy wrote:
Using the info from that website, I can code up the following to give
the two-tailed p-value of difference in correlations:
diff.corr <- function( r1, n1, r2, n2 ){
...
William Revelle also mentioned the r.test in the psych package. I would add here that inference on second-order quantities, such as correlation coefficients and variances, is not robust to the assumption of a normally-distributed population. (Inference on first-order quantities such as means and regression coefficients, IS pretty robust to that assumption.) A good general alternative is the bootstrap, implemented in R in the boot package. Norm Matloff